/********************************************************************* * * Filename: toim3232-sir.c * Version: 1.0 * Description: Implementation of dongles based on the Vishay/Temic * TOIM3232 SIR Endec chipset. Currently only the * IRWave IR320ST-2 is tested, although it should work * with any TOIM3232 or TOIM4232 chipset based RS232 * dongle with minimal modification. * Based heavily on the Tekram driver (tekram.c), * with thanks to Dag Brattli and Martin Diehl. * Status: Experimental. * Author: David Basden <davidb-irda@rcpt.to> * Created at: Thu Feb 09 23:47:32 2006 * * Copyright (c) 2006 David Basden. * Copyright (c) 1998-1999 Dag Brattli, * Copyright (c) 2002 Martin Diehl, * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * Neither Dag Brattli nor University of Tromsø admit liability nor * provide warranty for any of this software. This material is * provided "AS-IS" and at no charge. * ********************************************************************//* * This driver has currently only been tested on the IRWave IR320ST-2 * * PROTOCOL: * * The protocol for talking to the TOIM3232 is quite easy, and is * designed to interface with RS232 with only level convertors. The * BR/~D line on the chip is brought high to signal 'command mode', * where a command byte is sent to select the baudrate of the RS232 * interface and the pulse length of the IRDA output. When BR/~D * is brought low, the dongle then changes to the selected baudrate, * and the RS232 interface is used for data until BR/~D is brought * high again. The initial speed for the TOIMx323 after RESET is * 9600 baud. The baudrate for command-mode is the last selected * baud-rate, or 9600 after a RESET. * * The dongle I have (below) adds some extra hardware on the front end, * but this is mostly directed towards pariasitic power from the RS232 * line rather than changing very much about how to communicate with * the TOIM3232. * * The protocol to talk to the TOIM4232 chipset seems to be almost * identical to the TOIM3232 (and the 4232 datasheet is more detailed) * so this code will probably work on that as well, although I haven't * tested it on that hardware. * * Target dongle variations that might be common: * * DTR and RTS function: * The data sheet for the 4232 has a sample implementation that hooks the * DTR and RTS lines to the RESET and BaudRate/~Data lines of the * chip (through line-converters). Given both DTR and RTS would have to * be held low in normal operation, and the TOIMx232 requires +5V to * signal ground, most dongle designers would almost certainly choose * an implementation that kept at least one of DTR or RTS high in * normal operation to provide power to the dongle, but will likely * vary between designs. * * User specified command bits: * There are two user-controllable output lines from the TOIMx232 that * can be set low or high by setting the appropriate bits in the * high-nibble of the command byte (when setting speed and pulse length). * These might be used to switch on and off added hardware or extra * dongle features. * * * Target hardware: IRWave IR320ST-2 * * The IRWave IR320ST-2 is a simple dongle based on the Vishay/Temic * TOIM3232 SIR Endec and the Vishay/Temic TFDS4500 SIR IRDA transceiver. * It uses a hex inverter and some discrete components to buffer and * line convert the RS232 down to 5V. * * The dongle is powered through a voltage regulator, fed by a large * capacitor. To switch the dongle on, DTR is brought high to charge * the capacitor and drive the voltage regulator. DTR isn't associated * with any control lines on the TOIM3232. Parisitic power is also taken * from the RTS, TD and RD lines when brought high, but through resistors. * When DTR is low, the circuit might lose power even with RTS high. * * RTS is inverted and attached to the BR/~D input pin. When RTS * is high, BR/~D is low, and the TOIM3232 is in the normal 'data' mode. * RTS is brought low, BR/~D is high, and the TOIM3232 is in 'command * mode'. * * For some unknown reason, the RESET line isn't actually connected * to anything. This means to reset the dongle to get it to a known * state (9600 baud) you must drop DTR and RTS low, wait for the power * capacitor to discharge, and then bring DTR (and RTS for data mode) * high again, and wait for the capacitor to charge, the power supply * to stabilise, and the oscillator clock to stabilise. * * Fortunately, if the current baudrate is known, the chipset can * easily change speed by entering command mode without having to * reset the dongle first. * * Major Components: * * - Vishay/Temic TOIM3232 SIR Endec to change RS232 pulse timings * to IRDA pulse timings * - 3.6864MHz crystal to drive TOIM3232 clock oscillator * - DM74lS04M Inverting Hex line buffer for RS232 input buffering * and level conversion * - PJ2951AC 150mA voltage regulator * - Vishay/Temic TFDS4500 SIR IRDA front-end transceiver * */#include<linux/module.h>#include<linux/delay.h>#include<linux/init.h>#include<linux/sched.h>#include<net/irda/irda.h>#include"sir-dev.h"staticinttoim3232delay=150;/* default is 150 ms */module_param(toim3232delay,int,0);MODULE_PARM_DESC(toim3232delay,"toim3232 dongle write complete delay");#if 0static int toim3232flipdtr = 0; /* default is DTR high to reset */module_param(toim3232flipdtr, int, 0);MODULE_PARM_DESC(toim3232flipdtr, "toim3232 dongle invert DTR (Reset)");static int toim3232fliprts = 0; /* default is RTS high for baud change */module_param(toim3232fliptrs, int, 0);MODULE_PARM_DESC(toim3232fliprts, "toim3232 dongle invert RTS (BR/D)");#endifstaticinttoim3232_open(structsir_dev*);staticinttoim3232_close(structsir_dev*);staticinttoim3232_change_speed(structsir_dev*,unsigned);staticinttoim3232_reset(structsir_dev*);#define TOIM3232_115200 0x00#define TOIM3232_57600 0x01#define TOIM3232_38400 0x02#define TOIM3232_19200 0x03#define TOIM3232_9600 0x06#define TOIM3232_2400 0x0A#define TOIM3232_PW 0x10 /* Pulse select bit */staticstructdongle_drivertoim3232={.owner=THIS_MODULE,.driver_name="Vishay TOIM3232",.type=IRDA_TOIM3232_DONGLE,.open=toim3232_open,.close=toim3232_close,.reset=toim3232_reset,.set_speed=toim3232_change_speed,};staticint__inittoim3232_sir_init(void){if(toim3232delay<1||toim3232delay>500)toim3232delay=200;IRDA_DEBUG(1,"%s - using %d ms delay\n",toim3232.driver_name,toim3232delay);returnirda_register_dongle(&toim3232);}staticvoid__exittoim3232_sir_cleanup(void){irda_unregister_dongle(&toim3232);}staticinttoim3232_open(structsir_dev*dev){structqos_info*qos=&dev->qos;IRDA_DEBUG(2,"%s()\n",__func__);/* Pull the lines high to start with. * * For the IR320ST-2, we need to charge the main supply capacitor to * switch the device on. We keep DTR high throughout to do this. * When RTS, TD and RD are high, they will also trickle-charge the * cap. RTS is high for data transmission, and low for baud rate select. * -- DGB */sirdev_set_dtr_rts(dev,TRUE,TRUE);/* The TOI3232 supports many speeds between 1200bps and 115000bps. * We really only care about those supported by the IRDA spec, but * 38400 seems to be implemented in many places */qos->baud_rate.bits&=IR_2400|IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;/* From the tekram driver. Not sure what a reasonable value is -- DGB */qos->min_turn_time.bits=0x01;/* Needs at least 10 ms */irda_qos_bits_to_value(qos);/* irda thread waits 50 msec for power settling */return0;}staticinttoim3232_close(structsir_dev*dev){IRDA_DEBUG(2,"%s()\n",__func__);/* Power off dongle */sirdev_set_dtr_rts(dev,FALSE,FALSE);return0;}/* * Function toim3232change_speed (dev, state, speed) * * Set the speed for the TOIM3232 based dongle. Warning, this * function must be called with a process context! * * Algorithm * 1. keep DTR high but clear RTS to bring into baud programming mode * 2. wait at least 7us to enter programming mode * 3. send control word to set baud rate and timing * 4. wait at least 1us * 5. bring RTS high to enter DATA mode (RS232 is passed through to transceiver) * 6. should take effect immediately (although probably worth waiting) */#define TOIM3232_STATE_WAIT_SPEED (SIRDEV_STATE_DONGLE_SPEED + 1)staticinttoim3232_change_speed(structsir_dev*dev,unsignedspeed){unsignedstate=dev->fsm.substate;unsigneddelay=0;u8byte;staticintret=0;IRDA_DEBUG(2,"%s()\n",__func__);switch(state){caseSIRDEV_STATE_DONGLE_SPEED:/* Figure out what we are going to send as a control byte */switch(speed){case2400:byte=TOIM3232_PW|TOIM3232_2400;break;default:speed=9600;ret=-EINVAL;/* fall thru */case9600:byte=TOIM3232_PW|TOIM3232_9600;break;case19200:byte=TOIM3232_PW|TOIM3232_19200;break;case38400:byte=TOIM3232_PW|TOIM3232_38400;break;case57600:byte=TOIM3232_PW|TOIM3232_57600;break;case115200:byte=TOIM3232_115200;break;}/* Set DTR, Clear RTS: Go into baud programming mode */sirdev_set_dtr_rts(dev,TRUE,FALSE);/* Wait at least 7us */udelay(14);/* Write control byte */sirdev_raw_write(dev,&byte,1);dev->speed=speed;state=TOIM3232_STATE_WAIT_SPEED;delay=toim3232delay;break;caseTOIM3232_STATE_WAIT_SPEED:/* Have transmitted control byte * Wait for 'at least 1us' */udelay(14);/* Set DTR, Set RTS: Go into normal data mode */sirdev_set_dtr_rts(dev,TRUE,TRUE);/* Wait (TODO: check this is needed) */udelay(50);break;default:printk(KERN_ERR"%s - undefined state %d\n",__func__,state);ret=-EINVAL;break;}dev->fsm.substate=state;return(delay>0)?delay:ret;}/* * Function toim3232reset (driver) * * This function resets the toim3232 dongle. Warning, this function * must be called with a process context!! * * What we should do is: * 0. Pull RESET high * 1. Wait for at least 7us * 2. Pull RESET low * 3. Wait for at least 7us * 4. Pull BR/~D high * 5. Wait for at least 7us * 6. Send control byte to set baud rate * 7. Wait at least 1us after stop bit * 8. Pull BR/~D low * 9. Should then be in data mode * * Because the IR320ST-2 doesn't have the RESET line connected for some reason, * we'll have to do something else. * * The default speed after a RESET is 9600, so lets try just bringing it up in * data mode after switching it off, waiting for the supply capacitor to * discharge, and then switch it back on. This isn't actually pulling RESET * high, but it seems to have the same effect. * * This behaviour will probably work on dongles that have the RESET line connected, * but if not, add a flag for the IR320ST-2, and implment the above-listed proper * behaviour. * * RTS is inverted and then fed to BR/~D, so to put it in programming mode, we * need to have pull RTS low */staticinttoim3232_reset(structsir_dev*dev){IRDA_DEBUG(2,"%s()\n",__func__);/* Switch off both DTR and RTS to switch off dongle */sirdev_set_dtr_rts(dev,FALSE,FALSE);/* Should sleep a while. This might be evil doing it this way.*/set_current_state(TASK_UNINTERRUPTIBLE);schedule_timeout(msecs_to_jiffies(50));/* Set DTR, Set RTS (data mode) */sirdev_set_dtr_rts(dev,TRUE,TRUE);/* Wait at least 10 ms for power to stabilize again */set_current_state(TASK_UNINTERRUPTIBLE);schedule_timeout(msecs_to_jiffies(10));/* Speed should now be 9600 */dev->speed=9600;return0;}MODULE_AUTHOR("David Basden <davidb-linux@rcpt.to>");MODULE_DESCRIPTION("Vishay/Temic TOIM3232 based dongle driver");MODULE_LICENSE("GPL");MODULE_ALIAS("irda-dongle-12");/* IRDA_TOIM3232_DONGLE */module_init(toim3232_sir_init);module_exit(toim3232_sir_cleanup);